1. Field of the Invention
The present invention relates to a display device.
2. Description of the Related Art
High luminance, high color purity, and wide viewing angle are required of an organic electroluminescent display device. Moreover, for preventing the deterioration of an organic electroluminescent element, a sealing structure (JP 2015-23023 A) to seal out moisture and oxygen is generally provided, and a method for providing a multilayer structure including an inorganic film and an organic film has been proposed.
For achieving high luminance, high color purity, and wide viewing angle, attachment of an optical sheet or provision of an optical structure has been conventionally proposed (JP 2015-88322 A and JP 2012-507110 T). However, newly adding a layer involves, in addition to a cost problem, a problem of a reduction in light extraction efficiency due to increased interfaces (JP 2013-232279 A and JP 2014-86314 A).
The purpose of the sealing structure formed of the multilayer structure is to improve a covering property so that even when a foreign substance is present, a hole is not made, or to improve strength corresponding to flexibility, and a multilayer film is uniformly formed. In this case, reflection occurs at the interface between the inorganic film and the organic film, thus involving a problem of a reduction in light extraction efficiency.